matching springs to shocks

[55EXX]

how are springs matched to shocks? now i have heard how coil overs have springs matched to the shocks. my under standing would be harder shocks for lower springs to stop bottoming out etc. but if the coil over is damper adjustable then its not really a match right? you make it match for your driving style or drag track etc.

i have turned away from buying cheap d2 coilovers instead am getting kyb agx adjustable shocks for my eg. i have super low pedders springs and am happy with the ride height (does anyone know the spring rate?). i am able to adjust the damper much like a coilover set. so is there any advantage over having coilovers as opposed to my set up seeing as i am happy with its ride height?

[SeverAMV]

how are springs matched to shocks? now i have heard how coil overs have springs matched to the shocks. my under standing would be harder shocks for lower springs to stop bottoming out etc. but if the coil over is damper adjustable then its not really a match right? you make it match for your driving style or drag track etc.

i have turned away from buying cheap d2 coilovers instead am getting kyb agx adjustable shocks for my eg. i have super low pedders springs and am happy with the ride height (does anyone know the spring rate?). i am able to adjust the damper much like a coilover set. so is there any advantage over having coilovers as opposed to my set up seeing as i am happy with its ride height?

you can get non damper adjustable coilovers, like skunk2 pro-s series coilovers, which are really just a spring matched to a shock with height adjustable design.

the main difference between a matched spring and shock kit and a coilover kit is that with a coilover, you can adjust the height of the vehicle without having to change the spring, and all you will have to do is adjust the damper settings to match (on damper adjustables anyway). if you plan to take your car to the track, or plan to do some serious grip driving then height adjustable coilovers might have an advantage as the stiffer spring rates can help with grip, but if you're just doing daily driving and the occasional thrash, then theres no real benefit to upgrading.

[55EXX]

so only advantage is the height adjustablity? which for a track user is great to achieve a better roll centre and geometry etc. it would be a set and forget.

other advantage is stiffer spring rates but is that needed for any particular reason than less wheel travel and reducing body roll etc? i know roll resistance plays a roll with the spring rates and its bias but if this on my car was controlled by sway bars to achieve the balance i want what would be the advantage of me getting stiffer springs?

[SeverAMV]

with stiffer springs, when you corner, it requires more weight to shift to that particular side before it compresses more. ie. 8kg/mm will compress 1mm for every 8kg of force, so lets say an 80kg person gets in, it should drop 10mm. when you corner, weight shifts to the side. so the stiffer the spring rate, the less the spring compresses, which means a lesser chance of your suspension bottoming out and causing you to understeer, thus firmer spring rates can be more predictable to that extent. however, when you get snap oversteer with stiff spring rates, it really snaps out.

[SeverAMV]

with stiffer springs, when you corner, it requires more weight to shift to that particular side before it compresses more. ie. 8kg/mm will compress 1mm for every 8kg of force, so lets say an 80kg person gets in, it should drop 10mm. when you corner, weight shifts to the side. so the stiffer the spring rate, the less the spring compresses, which means a lesser chance of your suspension bottoming out and causing you to understeer, thus firmer spring rates can be more predictable to that extent. however, when you get snap oversteer with stiff spring rates, it really snaps out.

the whole set up is really up to you. but if you've already got springs and shocks, and you like it already, dont bother getting coilovers. just get sway bars and strut bars to complete your package. you'll save more money and you'll corner better than if you were to just ditch the springs and shocks for coilies and nothing else.

[55EXX]

thats not the complete reason why i figured out why.

[SeverAMV]

there are also exact science reasons why as well, but you dont really need to know all of that. you just need to stick with what you like and what feels good to you, because that way you'll have a setup that matches your driving style.

[55EXX]

basically the spring pushes down on the wheel keeping it in contact with the road. your dampers control how this spring moves. putting all sways roll centres over/understeer balance aside the spring and shock are the most basic pair. the spring is what rate is how much energy the spring takes to compress but also the force it presses down. by increasing damper rate it takes more control over the springs movement. with out a damped enough spring it will continue to bounce. with a too damped spring the wheels movement will become too damped and the spring won't be able to push down hard and fast enough to retain good contact on the ground becoming lazy. so by increasing your dampening a higher spring rate is needed to match that dampening level = better handling + harder ride

shocks have no effect on under/oversteer during static/mid corner. it tho has a great effect on turn in response. alot of people use a damper that is alot harder at the rear for the reason the the arse will stay flatter when driving into a turn so it has less understeer but by mid corner the shock has come to rest in the same spot a softer shock has but just got there at a slower rate. much like a rear sway but only for a second during turn in. advantage being it doesn't affect steering balance but has better turn in.

hieght adjustment has 2 major changes. change in centre of gravity and change in roll centre. with out too much detail roll centre is another factor contolling body roll and therefore over/understeer. this can be a factor often neglected because many like myself opt for the use of sway bars and spring rates to control bodyroll and under/oversteer balance.

i could go into more detail but thats the basic jist of it